Apparatus and method for preparation of artificial dentures



Dec. 23, 1958 5 Sheets-Sheet 1 INVENTOR ls aseph Zelmgher ATTORNEi J. ZELNIGHER APPARATUS AND METHOD FOR PREPARATION OF ARTIFICIAL DENTURES Filed March 16, 1955 J. ZELNIG Dfli. 23, 55

R PREPARATION OF ARTIFICIAL DENTURES APPARATUS AND METHOD Filed March 16, 1955 5 Sheets-Sheet 2 INVENTOR ATTORNEY METHOD FOR PREPARATION 5 sheets-sheet 5 FIG. 9

FIG. IO

INVENTOR Joseph .Zelmgher ATTORNEY Dec. 23, 1958 J. ZELNIGHER APPARATUS AND 0F ARTIFICIAL mmwunss Filed March 16, 1955 J: a. TE 3. 3 2 I APPARATUS AND METHOD FOR PREPARATION OF ARTIFICIAL DENTURES Joseph Zelnigher, Savannah, Ga. Application March 16, 1955, Serial No. 494,682

9 Claims. (Cl. 32 32 This invention relates to a device for use in dental prosthesis and more particularly to a device for use in the making of artificial dentures.

In present day practice the production of artificial dentures is largely an art, depending for success upon the skill and experience of the one carrying out the production. Because of this fact, it is generally not possible to assure results to a patient before the denture has actually been made. And yet the traditional method persists because of the notion that each case is different from any other, in all respects, except for coincidence.

I have found that there are certain fixed anatomical relationships which are the same in virtually all mouths, and with the aid of these fixed relationships it is possible to reduce the dependence in denture making on skill and experience. By the use of my invention which utilizes these fixed relationships, it will be possible to be far more certain of successful results in making a particular denture with the expenditure of considerably less effort.

It is, therefore, the primary object of this invention to provide a device whereby a new and much improved tech nique may be used in the building of artificial dentures. The new technique parallels the old to the point of preparing a maxillary cast, a corresponding base plate and bite rim or its equivalent, and thereafter departs from the old technique. Following such preparation the maxillary cast is generally positioned in an articulator, and thereafter teeth installed in the base plate. It is at the step of positioning the cast in the articulator that considerable skill and experience is required, and where the greatest chance of' error lies when such step is carried out strictly by eye or by known aids, such as a face bow. Rather than relying purely on the eye, or on a face bow transfer for positioning the maxillary cast in the articulater, my device utilizes certain fixed anatomical points for the mounting of the maxillary cast. Thus, an edge is provided on which the two hamular notches, which are present in every mouth, rest. A third fixed point is determined as the medial point on the crest of the ridge at the front of the cast. Utilizing these three points, an accurate positioning of the cast, corresponding closely to the position in the mouth, is achieved speedily and without the use of extrinsic aids.

A further object of my invention is to provide a means for setting up of teeth on the base plate, which means makes for speedy yet accurate set up. This object is carried out by providing that the means for positioning the maxillary cast be removable, and replaceable by a second means in the nature of a swivelable templet, against which teeth may be set.

Still another object is to provide for adjustability of the cast positioning means as to vertical height, and within this object, means for so determining the vertical height of the upper cast, etc., when mounted, that when the templet is substituted for the cast positioning means, the distance between templet and cast be proper.

Another object of my invention is to make possible a corrective adjustment whereby the structure embodying my invention may have flexibility. Within this object is embraced a provision for variations in vertical as well as angular positioning of the templet means, so that the practitioner is not limited to a rigid setting once the upper cast is plastered into position. Moreover, by permitting an angular adjustment of the templet, corrections for purposes of achieving a pleasing aesthetic result, and greater mechanical efliciency may be accomplished.

Another object herein is to make it possible to carry out with ease all adjustment and interchange of parts.

Finally, it is an object herein to so fashion my structure that it may easily be adapted for use with any dental articulator.

How these and many other objects are to be implemented will become apparent through a consideration of the accompanying drawings wherein;

Fig. 1 is a plan view of the apparatus with the position ing member in place;

Fig. 2 is a front view of the same;

Fig. 3 is a side view of the same;

Fig. 4 is a section at 44 of Fig. 2;

Fig. 5 is a section at 55 of Fig. 2;

Fig. 6 is a plan view of the templet member;

Fig. 7 is a side view showing the templet member mounted in the base block;

Fig. 8 is a section at 88 of Fig. 6;

Fig. 9 is a side view of a maxillary cast with mating base plate;

Fig. 10 is a side view of a base measuring the same, and

Fig. 11 is a section at 11--11 of Fig. 10.

The foundation of the embodiment of my invention shown in the drawings is the base member 10 which has a base block 11 and table 12 mounted within and elevatable with respect to said base block. The base block is appropriately drilled to slidably accommodate guide legs 13 fixedly mounted in the underside of table 12, which guide legs serve to preserve horizontality when said table is raised or lowered by means of rack Maud pinion 15, the rack being fixedly mounted at one end in the under side of table 12. Pinion 15 may be rotated by a wrench brought into engagement with socket 151;. Locking nut 16 is threaded into base block 11 to engage rack 14 and prevent any change of position of table 12 relative to the base block once a proper setting has been made. A Vernier scale 17 is provided in the base block which together With marking 18 inscribed on one of legs13 furnishes a convenient means for exactly regulating movement of table 12.

In the topside of table 12 is formed a keyway 19 for the alternate accommodation of members of the device hereafter to be described. At the rear of base block 11 are sockets 20 whereby holder member 24 may be releasably held in position relative to the device.

The holder member 24 has plugs 25 for engagement with sockets 20. The plugs 25 are set into and form a part of a bracket 26 having engaging hooks 27 and a spring loaded plunger 28 which can hold the holder 29 proper in secure yet releasable engagement with the hooks 27. a

The keyway 19 in the top of table 12 is suitable for engagement with the keyed foot 32 of the positioning member 33, which has a basic frame 34 having finger grips 35 by means of which the positioning member 33 may be easily manipulated. The positioning member 33 may be locked in position in keyway 19 by means of set screw 35a. Rotatably mounted on the frame 34 is the rotatable pinion 36 which engages a pair of racks 37 by means of which the knife edge member 38 carrying knife edges 39 may be raised or lowered. The pinion 36 may be rotated by application of a Wrench to socket 37a. A locking nut 40 may be used to fix the position of the knife plate and caliper for edges relative to the frame when a proper setting has been reached.

Extending normal to the knife edges is rod 41, a portion 42 of which is threaded to permit engagement with threaded passageway 43 of knife edge member 38, whereby the rod 41 may be made to protrude to a greater or lesser extent through knife edge member 38. Rod 41 is pointed at end 44, and has a knurled head 45 at its other end for ease in rotation of the rod. A vernier scale 46 is provided on frame 34, and a mark 47 inscribed on a rack 37 whereby the vertical positioning of knife edge member 38 relative to the frame 34 may be accurately determined.

The positioning member 33 may be removed from table 12 and its place taken by templet member 50, which similarly has a keyed foot 51 for engagement with keyway 19, the keyed foot 51 being shorter than keyway 19 to permit the varying placement of the templet member on a horizontal plane within the keyway. Once a position withinthe keyway has been selected, the templet member may be locked in position by means of set screw 51a. Pierced and threaded brackets 52 comprise part of the keyed foot 51, and the templet proper, 53, is pivotally mounted to the foot by means of a pierced lug 54 which fits between brackets 52, in such manner that when locknut 55 is threaded therebetween the templet may be swivelled relative to the foot, and frictionally locked in proper position. Marks 56 may be inscribed on brackets 52 to match with mark 57 inscribed on the lug 54, whereby a preferred or base pivotal position may be easily established for the templet, as may be seen in Fig. 8.

It should be noted that I find it convenient in my structure to provide that locknuts 16, 40, and 55, and the heads of pinions at 15a and 37a all have uniform openings, as for example, hexagonal openings so that a single wrench may be used to manipulate all locking nuts and pinions.

The structure described above is admirably suited to the setting up of teeth for artificial dentures. In carrying out the process of making dentures through use of my device, it is necessary as in present day practice to first make a maxillary cast 60 and upon that construct a base plate 61 having formed thereon a wax bite rim 62 or other indication of the proper extent of protrusion of teeth below the lip at rest. The top surface of the base plate mates with the cast of the upper gum structure. By means of a caliper, a measurement is then taken of the dimension between the top surface 63 of base plate 61 and the lower edge of bite rim 62, as in Fig. 10. The caliper 64 which is provided for taking this dimension is uniquely constructed having a calibrated rule 65 at the lower extremity of which is foot 66 to engage the bite rim surface. Mounted upon the rule is the slide 67, having an L-shaped extension 68, the terminal edge 69 of which coincides in spacing from foot 66 with that of the lower edge of the slide 67. Thus, when bite rim 62 is placed upon foot 66, and terminal edge 69 of the L-shaped extension is brought into contact with the top surface 63 of the base plate, a reading on the rule 65 is obtained which corresponds to the distance from the midpoint of the anterior portion of the cast to the limit of extent for teeth substantially as this limit will appear in the final denture.

The foot 32 of positioning member 33 is. placed into the keyway 19 in the top of table 12, and locked in position by set screw 35a. The measurement just determined with the caliper is set on vernier scale 46 so that the knife edges 39 assume the vertical position indicated by this measurement, and the knife edge member 38 is locked in position by tightening locknut 40, a cast 60 having hamular notches 70 and a midpoint 71 on the anterior portion of the cast without a baseplate is then placed upon the positioning member 33 in such manner that the hamular notches rest upon knife edges 39 and the midpoint 71 rests upon rod 41 as in Fig. 3. (The pointed end 44 of the rod is provided for the set-up of cases where natural front teeth remain in the mouth, and also for the set-up of finished dentures for testing. In such cases, the point will engage the space between the central teeth at the gum line.)

The cast having been positioned, and the holder member mounted on the base block 11, the cast is plastered to holder 29. After the cast has been thus mounted, the positioning member is removed from the device, and the templet member substituted therefor in the keyway 19 as in Fig. 7, and locked in position. Because the knife edges 39 are adjusted as to vertical height as already indicated, the mounted cast is automatically positioned at an appropriate distance above the templet 53 so that artificial teeth may be rapidly set into a base plate against the templet. While it may be found that with many cases a single angular position of templet 53 relative to the top of table 12 will suffice, provision, as has already been described, has been made for varying this angular position for those cases where it is required.

Similarly, it may be found that the vertical spaced relationship between the mounted cast and the templet surface will be preferably correct in most cases. However, since it is not possible to change the vertical position of the cast once mounted, where mounting is done by plastering, and because on occasion it will appear desirable to alter the spacing between cast and templet after the cast has been mounted the table has been made elevatable and depressable by the provision of rack 14 and pinion 15 whereby corrections may be made.

I wish to mention also that I contemplate that it may be advantageous to make the surface of templet 53 against which teeth are set, or to imbed in such surface, abrasive whereby after teeth are mounted they may be manually ground down on manipulation against the abrasive surface.

While I have described a specific embodiment of my invention it is apparent that changes and modifications may be made therein without departing from the spirit of my invention.

I claim:

1. A device for use in the construction of artificial dentures including a holder upon which a maxillary cast may be mounted, and positioning means whereby said cast may be positioned for mounting on said holder, said positioning means having a knife edge for providing colevel support to the hamular notches of said maxillary cast and a rod having a free end extending normal to said knife edge to support the endpoint of the anterior portion of said maxillary cast.

2. A device as claimed in claim 1 including means whereby the distance between said free end of said rod and said knife edge may be varied.

3. A device as claimed in claim 1 wherein said rod terminates in a point at said free end.

4. A device for use in the construction of artificial dentures including a holder upon which a maxillary cast may be mounted, positioning means whereby said cast may be positioned for mounting on said holder, said positioning means having a plurality of points for supporting said maxillary cast, two of said points being co-level for engagement with the hamular notches of said cast, and a base member having a table thereupon, said positioning means being mountable upon said table.

5. A device for use in the construction of artificial dentures including a holder upon which a maxillary cast may be mounted, positioning means whereby said cast may be positioned for mounting on said holder, said positioning means having a plurality of points for supporting said maxillary cast, two of said points being co-level for engagement with the hamular notches of said cast, and a base member having a table thereupon and including a vernier scale therein, said table being adjustable as to height and lockable at a selected position on said vernier scale, said positioning means being mountable upon said table.

6. A device for use in the construction of artificial dentures including a holder upon which a maxillary cast may be mounted, positioning means whereby said cast may be positioned for mounting on said holder, said positioning means having a plurality of points for supporting said maxillary cast, two of said points being colevel for engagement with the hamular notches of said cast, and a base member having a table thereupon, said positioning means being mountable upon said table, said plurality of points being vertically movable relative to said table.

7. A device for use in the construction of artificial dentures including a holder upon which a maxillary cast may be mounted, positioning means whereby said cast may be positioned for mounting on said holder, said positioning means having a plurality of points for supporting said maxillary cast, two of said points being colevel for engagement with the hamular notches of said cast, and a base member having a table thereupon, said positioning means being mountable upon said table and including a Vernier scale, said plurality of points being adjustable as to height to a predetermined setting on said Vernier scale.

8. A device for the use in the construction of artificial dentures including positioning means having a plurality of points for supporting a maxillary cast, two of said points being co-level for engagement with the hamular notches of the cast, and a base member having a table thereupon, said positioning means being mountable upon said table.

9. A device as claimed in claim 8 including a knife edge in said positioning member, said two co-level points occurring on said knife edge.

References Cited in the file of this patent UNITED STATES PATENTS 1,931,804 Sanborn Oct. 24, 1933 

